Why is Christ referred to as our righteousness?

In Scripture, Christ is referred to as 'the Lord our righteousness' (Jehovah Sidkenu) because He met the demands of God's law that we could never fulfill. His perfect obedience and sacrificial death provide the only way for us to be declared righteous before God. As believers, we rest in the fact that our righteousness is not of our own doing but is credited to us through faith in Christ. This truth assures us that we are accepted by God based solely on His grace and through the merits of Christ's accomplished work.